Blower



May 23,l 1944- w. M. MARKER ET AL BLOWER W P M M May 23, 1944- w. M. MARKER ET AL 2,349,668

BLOWER Filed Aug. 2, 1940 2 Sheets-Sheet 2 Zin/anfora @www N Patented May 23, 1944 BLOWER William M. Marker, Los Angeles, and Andrew G.

Orear, Glendale, Calif., assignors to` Trade- Wind Motorfans, Ine., Los Angeles, Calif., a corporation of California Application August 2,1940, Serial No. 349,387

l Claims.

This invention relates to a blower and relates more particularly to a blower adapted for installation in the kitchens, bathrooms and other compartments and rooms of residences, clubs, oilces, restaurants, etc. A general object of this invention is to provide a compact, easily installed blower that is quiet and very ellcient in operation.

Another object of this invention is to provide a blower proportioned and designed for installation in the joist spaces, stud spaces and similar wall, ceiling and partition spaces of residences and other building structures and embodying highly efficient centrifugal type or squirrel cage blower wheels to assure the maximum delivery or removal of air with a minimum of sound.

Another object of this invention is to provide a blower of the character referred to that is in the form of a single, compact unit having a single case for the motor, blower compartments, blower wheels, and other parts.

Another and important object of the invention is to provide a blower of the character referred to which may be positioned and conditioned to discharge the air vertically or to discharge the air horizontally at either side of the case without making time consuming alterations in the structure, duct system or building structure. The improved blower of the present invention is universally adaptable tok practically all installation spaces and conditions and a single type or model is adaptable for all intended uses, making it unnecessary, to manufacture vertical types, horizontal types, etc. A

Another object of this invention is to provide a blower of the character mentioned embodying novel interchangeable closure means and discharge-duct adapter means making the unit adaptable for both vertical and horizontal duct connections when installed in a ceiling, or the like.

Another object of the invention is to provide a blower of the character mentioned in which the motor and blower wheels form part-s of an assembly or unit that may be bodily removed from the case with ease to facilitate cleaning, lubricating and servicing.

Another object ofthis invention is to provide a blower of the character referred to embodying means for cooling the motor by air drawn o1' induced from an attic space, stud space, or from the exterior of the building so that the motor is maintained at a low temperature for efficient cptaminated air of the kitchen or other compartmentbelng ventilated.

Another object of the invention is to provide a blower of the character referred to in which the motor is fully protected and isolated'from the moisture bearing, grease bearing and dust bearing air from the ventilated room or compartment.

A further object of the invention is to provide a simple, inexpensive blower of the character referred to embodying effective means for dampening vibration of the moving parts.

The vvarious objects and features of our invention will be fully understood from the following detailed description of a typical, preferred form and application of the invention, throughout which description reference is made to theV accompanying drawings, in which:

Fig. l is a perspective view of the blower provided by this invention showing the inlet grill and the duct adapter at one side of the case. Fig. 2 is a perspective view of the blower showing the closure at the top of the case and the duct adapter at the side of the case. Fig. 3 is an enlarged, vertical, detailed, sectional View of the central portion of the blower', showing the motor and other parts in elevation. Fig. 4 is an enlarged, fragmentarmvertical, detailed, sectional view taken as indicated by line l-I on Fig. 3 with the motor and blower wheels in elevation. Fig. 5 is a perspective view of the blower case.

'I'he improved blower of the present invention may be said to comprise, generally, a housing or case i0, means il on the case I0 adapting the same for either vertical or horizontaldischarge duct connections, and a removable and shiftable motor and blower wheel unit in the case Ill comprising a blower chamber and supporting structure I2, a motor i3, and blower wheels I4.

The case lil serves to house and support the various other parts of the blower and is designed for installation iii the joist spaces and stud spaces oi the ceiling, wall, partition, or like part of a building structure. In the following description it will be assumed that the case ill is positioned as installed in a ceiling, in which case it has a top I5, sides I8 and ends I1. The case l0 is a hollow, box-like, generally rectangular structure and its lower end is open to form the air inlet and to facilitate the insertion, removal and servicing of the motor and blower wheel unit. kThe case i0 may be formed of sheet metal and its several parts may be welded together or otherwise connected. Means is provided for facilitating the ready installation of the case lll.r The metal of the case sides I8 is turned up along the lower edges of the sides to lie flush against their external surfaces and is then turned out or horizontally to present horizontal securing flanges I8. Strips I9 of sheet metal and oi' angular shape are arranged against the lower edge portions of the case ends I1 to present outwardly directed horizontal flanges 20. The strips I9 may be curled or rounded over the lower edges of the ends |1 and welded to the ends. The flanges 20 lle in the same horizontal plane as the ilanges I8 to form continuations of the ilanges I8 and corner strips 2| connect the flanges I8 and 20 at the corners of the case I to Astrengthen the structure. lThe flanges I8 and 20 may have spaced openings for the reception of nails, screws, or other attaching means. It is usually preferred to provide strips'of wood or a wooden frame (not shown) at the opening in the wall or ceiling which is to receive the ventilator and the anges I8 and 20 may be secured to such strips or frame to Vmount the ventilator. f

One side I6 of the case I 0 is provided with a series of louvers 22 spaced midway between its ends and preferably formed to face downwardly at the exterior of the case. The other side I of the case I 0 and the case top I5 have two spaced slots or openings 23. The openings 23 are rectangular and of the same size. The elongate openings 23 are equally spaced at opposite sides of the central vertical plane of the case I0 and in the particular arrangement shown they adjoin and are continuous, each opening extending into both the top I5 and the sides I6. It will be apparent that the openings might, in some cases, be spaced apart. The slots or openings 23 preferably have portions oi' equal length in the top I 5 and side I6.

The means II for adapting the case I0 for either vertical or horizontal air discharge duct connections is a feature of the invention. I'he means I I serves to cover or close portions oi' the above described openings 23, while facilitating the connection of a discharge duct with the onen or uncovered portions oi' the openings. The means II preferably includes guides or retaining strips 24 on the case top I5 and the case side I6 adjacent the openings 23. The strips 24 may be formed of sheet metal and the two strips may be identical. The strips 24 are U-shaped in plan or face view, each having arms or side parts extending in parallel relation to the outer walls of the openings 23 and a transverse or connectingr part extending along the case I0 at the ends of the openings. It is preferred to space the strips 24 from the openings 23. As best illustrated in Figs. 3 and 4 of the drawings, the strips 24 are formed or bent so that their inner marginal portions 24a are clear of or spaced from the external surfaces of the case III.

The means II further includes a transferable closure 25 and duct adapter 26. The closure 25 may be a simple, flat, rectangular sheet metal member, proportioned to be slid under the raised portions '24 of the strips 24 to cover the portions of the openings 23 at the top I5 or the case side I6. The duct adapter 26 comprises a rectangular sheet metal member adapted to be slid under the strip portions 24l and provided with spaced openings 21 i'or registering with portions of the openings 23. A ilange 28 extends along one longitudinal edge of the adapter 26 and this flange is adapted to be arranged at either the case top I5 or the case side I6 depending upon the location of the adapter. The flange 28 may be an ing end ilanges 31 integral part of `the adapter 2l. An outwardly projecting rim or flange 28 is provided on the adapter 26 to surround the openings 21 and the portion of the adapter between the openings. One longitudinal part oi' the flange 23 may be an integral portion of the flange 28 turned back and extended from the outer side ot the adapter, while the remaining sides oi' the flange 2l may be shaped from a single continuous strip of sheet metal flanged and welded to the adapter and connected with the first mentioned longitudinal portion. In the drawings we have shown the flange 29 of rectangular form to receive or extend into the end portion of a correspondingly shaped discharge duct or discharge duct fitting. it being understood that the flange 23 may be cylindrical or shaped as desired. 'I'he openings 21 of the adapter 26 are located and proportioned to have full communication with the portions oi' the cese openings 23 at the case top I5 or side I5 when the adapter is in its proper position under a retaining strip 24. f

The closure 25 and the adapter 25 are interchangeable, that is, either one may be engaged under the strip 24 at the top I5 or at the lcase side I6. When the closure 25 is arranged at the case top I5 and the adapter 23 is arranged at the side I6, as illustrated in the drawings. the case Il) is conditioned for connection with a horizontally extending air discharge duct. With the adapter 26 engaged in the strip 24 at the case top I5 and the closure 25 engaged with the strip 24 at the case side I6, the ventilator is conditioned for connection with a vertically extending air duct. Openings 30 are formed in the outer edge portion of the closure 25 and the ilange 28 of the adapter 26 to communicate with one another and to communicate with correspondingly located openings 3| in the case top I5 and side I6. A screw or bolt 32 is passed through the openings 30 and one of the openings 3| to hold the closure 25 and the adapter 26 in position. It is believed that it will be apparent how the ventilator case I0 may be readily and quickly conditioned for connection with either a horizontal or vertical air duct. The closure 25 and the adapter 26 are rather closely fitted under the strips 24 and are retained by the screw 32 so that they cannot work or vibrate.

The structure I2 provides or defines the motor chamber 33 and the blower chambers 34 and supports the motor I3 and the blower wheels I4. In accordance with the invention the structure I2 is easily inserted in and removed from the case III and is adapted to be positioned to direct the air either upwardly or horizontally depending upon the location of the adapter 26. The structure I2 includes a pair of spaced rectangular substantially vertical plates 35. The plates 35 are connected by spaced straps or bands 36 havsecured t0 the plates by bolts 38. 'I'he plurality cf straps 36 is arranged in a horizontal circular series. A connecting member 39 somewhat wider than the straps 35 extends between the plates 35 and has end flanges secured to the plates by bolts 40 to assist in connecting the plates 35. The plates 35 have central openings 4| and are dished or pressed out around the openings 4I at 42 to increase their rigidity and' to better receive the motor I3. The space between the plates 35 constitute the motor chamber 33.

The structure I2 further includes scroll sheets 01 VQllltC members 42 at the outer sides of the plates 35. The volute members 42 are formed of sheet metal and are secured in corresponding positions to the outer sides of their respective plates 35. 'I'he inner edges of the volute members 42 have out-turned flanges 43 integrally joined to the plates 35 by welding. -With this arrangement the `plates 35 close the inner ends of the blower chamber 34 except for their openings 4 I. End plates 44 are arranged on the outer sides of the volute members 42. The plates 44' have marginal inturned flanges 45 shaped to conform and t within the volute members 42. The flanges 45 are preferably welded to the members 42. It ywill be observed that the volute members 42 welded at their opposite ends and throughout their curved margins to the plates 35 and 44 provide a very strong, rigid assembly.

'I'he volute members 42 and the end plates 44 have their outer edges at corresponding edges of the plates 35 adjacent one corner of the assembly. This is shown at 46 in Fig. 3. Angular cut-off parts 4l are arranged between the plates 35 and 44 at the inner ends of the volute members 42 and are shaped to form inner extensions of the members to increase the efliciency of the blower. The cut-o parts 41 are shaped to extend outwardly to the adjacent edges of the plates 35 and 44. The plates 35 and 44, the outer portions of the volute members 42 and the cuto parts 4l define rectangular outlets 48 for the blower chambers 34. The cut-off parts 47 may be welded to the adjacent portions of the plates 35 and 44 and the scroll members 42. The above mentioned blower outlets 48 are of the same shape and size as the adapter openings 2l and are located to directly communicate with the openings 21 with the structure I2 in its different positions. The end plates 44 yof the blower chambers 34 have openings 49 concentric with the openings 4I and proportioned to permit the insertion of the blower wheels I4. Inlet fittings 56 are arranged on the outer sides of the plates 44 at the openings 48 and are secured to the plates by screws 5I, or the like. Inwardly curved lips 52 are formed on the fittings and extend through the openings 49 to provide stream-lined inlets for the blower wheels I4.

Means are provided for guiding the structure I2 into the case I8 and for securing the structure in the case. Spaced vertical angular strips 53 are provided on the inner surfaces of the case top I5 and sides I6 to cooperate with and guide the spaced plates 35 of the structure I2. The strips 53 assist in holding the structure I2 in the position where the end plates 44 are spaced a substantial distance from the case ends Il. The volute members 42 are likewise spaced substantial distances from the case walls. With the plates 44 and the members 42 spaced from the internal walls of the case I0 the air is free to flow upwardly through the case I0 to the inlet lips or mouths 52 of the blower chambers 34. The structure I2 is adapted to be positioned in the case I6 to have its outlets 48 face either vertically or horizontally. As shown in the drawings, the structure I2 is arranged to have the -outlets 48 face horizontally so that they communicate with the openings 21 of the adapter 26, which is secured to the side of the case I0. If

the adapter 26 is secured to the case top I5 the structure I2 is removed from the case I0, with the motor I3, wheels I4, etc., mounted therein, and is turned end for end and side for' side to bring the air outlets 48 into registration with the openings 21 of the adapter 26.' In either position of the structure I2 the plates 35 are guided by or Acooperate with the strips 53.

The means for removably securing the motor and wheel supporting structure I2 in the case I8 includes brackets 55 secured to the inner surfaces o1 the case sides I6 between the guide strips 53. Studs 56 are secured to the brackets 55 and project downwardly therefrom. A retainer plate or cover 51 is arranged across the lower end of themotor chamber 33 and has openings 58 passing the s tuds 56. Wing nuts 5g are threaded on the lower ends ofY the studs 5 to the plates 35 are adapted to bear on the retainer or cover 5`I` to support the structure I2in the case I8. It is preferred to provide the retainer or cover 51 with up-turned flanges 60 to cooperate with the outer sides of the plates 35 for the purpose of steadying the structure I2 and for preventing endwlse movement of the structure. The supporting member or cover 5'I may be reinforced by strips 6I secured to its inner side. The cover 5I closes the lower side of the motor chamber 33 to prevent the moisture and I grease laden air handled by the device from contacting the motor I3. The cover 51 also serves to prevent lubricant from the motor from dripping out of the device.

The 'motor I3 serves to drive or rotate the blower wheels I4 in the chambers 34. The motor I3 is of any selected type and of suitable rating. As illustrated the motor I3 is positioned horizontally in the chamber 33 to have its shaft 62 in co-axial relation with the openings 4I. The opposite ends of the motor I3 are spaced from the plates 35 being received in the concave plate portions 42 with considerable clearance. The shaft 62 extends from each end of the motor I3 to project into the blower chambers 34. The driving motor I3 is supported in the series of straps 36 by an effective. Vibration dampening and absorbing means. The straps 36 have spaced openings 63 and grommets or thimbles 64 of rubber, or the like, are set in the openings 63. The thimbles 64 project from the inner 'and outer vsurfaces of the-straps 36 and are grooved to receive the portions of the straps surrounding the openings 63. Bolts or studs 65 are threaded in the housing of the motor I3 to have their heads received in the thimbles 64. The heads of the studs 65 dependably retain the vthimbles 64 in the openings 63. The motor I3 supported by the spaced pairs or sets of yielding thimbles 64 is free floating and is insulated or isolated from the structure I2 by the thimbles so that vibration due to its operation and the operation of the wheels I4 is not transmitted to the structure. A suitable capacitator 66 for the motor circuit is secured to the member 39 by a suitable strap or clip 61.

Novel means is provided for supplying the energizing current to thev motor I3. A suitable junction box 68 is secured in the case I0. The box 68 is preferably arranged in the motor charnber 33 above the louvers 22 at the juncture of the upport the cover 5l. The lower edges of plug 12.

cable' or line 1| comprising the motor leads extends from the motor I3 and is provided with a The plug is adapted to be engaged or Suitable lubricant fittings or oil cups 86 are 1 provided on the motor I3. The cups 60 are preferably positioned at the upper side of the motor.. and are spaced approximately 45 from the central vertical plane of the motor to be in generally upright positions when the structure I2 is arranged in either of its positions described above.

The blower wheels I4 are mounted on the motor shaft 62 to rotate in the chambers 34. The wheels I4 are centrifugal or squirrel-cage type blower elements. Each wheel I4 includes a hub 13 xed to the motor shaft 62 and a disc or end plate 14 secured to the inner end of the hub.

Y The hubs 13 are secured to the motor shaft 62 to have the end plates 14 adjacent but spaced from the plates 35. The wheqs I4 further in. clude annular or tubular series o'f axially extending blades 15 secured to the peripheral portion of the plates 14. The blades 15 extend outwardly toward the plates 44 and are connected at their outereends by rings 16. The outer ends of the wheels 14 are immediately adjacent the inlet ilttings 50 to directly receive the air from the inlet lips 52. The centrifugal wheels I4 operate inthe well known manner to pick up the air and whirl it rapidly for expulsion through the discharge openings 48. The wheels I4 mounted on the opposite end portions of the motor shaft 62 balance the motor to provide for better motori` operation.

It is usually preferred to provide a suitable grill 11 at the inlet side or open lower end of the case I0. The grill 11 may be of any selected design and is applied to the case I0 following the insertion of the structure I2. In practice the grill 11 may be larger than the lower end oi the case I0 to have its edge portions overlie and engage the ceiling surface or frame around the case Ill. The grill 11 may be secured in place for easy removal `by any selected means.

It is believed that the operation of the device of the present invention will be readily understood from the foregoing detailed description. The housing I0 is designed for ready installation in the joist spaces of a ceiling, partition, wall, or the like. When the installation conditions have been ascertained the case I0 is adapted or adjustedl for connection with a vertical discharge duct or a horizontal discharge duct, as the case may be. Where the structure is to be installed in the ceiling for connection with a horizontal duct, the closure is arranged at the case top I5 and the adapter 26 is provided on the case side I6, as illustrated throughout the drawings. If the structure is to be connected with a vertical duct the positions of the closure 25 and adapter 26 are reversed, that is, the closure 25 is arranged at the case side I6 and the adapter 26 is provided at the case top I5. The closure 25 and the adapter 26 are easily engaged under the strips 24 and 'secured by the bolt 32.

When the case I0 has been installed and the power leads have been connected with the terminals of the socket 10, the structure I2 carrying opening in a second side, and a blower wheel the motor I3 and the wheels I4 is installed in j the case III. The' direction of air discharge is, of

course, known and the unit I2 is positioned to have the discharge passages 48 communicate with the adapter openings 21. As described above, the structure I2 may be turned end for end and side for side to bring it into'position for mounting in the case I0 with the adapter 26 in either of its positions. The structure I2 is easily passed into the lower end' oi.' the case I0 and secured in place by the retainer or cover 51 and its wing nuts 59. The plug 12 is engaged in the socket 10 to connect the motor I3 with its power source.

'Ihe grill 11 is then mounted in place to complete the installation.

'I'he structure I2 is a strong, rigid unit made up of integrally connected parts formed and related to provide the "greatest possible rigidity. The motor I3 isl supported by the vibration dampening thimbles 64 so that little or no vibration is transmitted to the structure I2 of the case Ill. 'I'he wheels I4 operating in the two chambers -34 continuously draw air through the lower end o! the case I0 and discharge it through th'e openings 21. 'I'he motor I3 is cooled by a stream of air drawn through the louvers 22 and the chamber 33 and induced through the openings 4I into the main air streams. This motor cooling air is drawn from the attic, joist space, or the like, so

lthat the motor is not soiled or injured by the moisture bearing, grease bearing, and dust bearing air received from the kitchen or other compartment being ventilated. When it becomes desirable or necessary to service or lubricate the ventilator the grill 11 is removed and the wing nuts 59 are removed to permit the with'drawal of the structure I2 from the case I0. The lubricant ittings or cups 60 of the motor I3 may be provided with lubricant and the apparatus may be serviced in other respects, whereupon the unit I2 maybe re-installed in the case I0.

Having described only a typical preferred form and application of our invention, we do not wish to be limited or restricted to the specic details herein set forth, but wish to reserve to ourselves any variations or modications that may appear to those skilled in the art or fall within the scope of the following claims. y

Having described our invention, we clatim:

l. A blower for installation in a ceiling space, or the like, comprising a case to be xed in said space and having an open lower end and having openings in its top and a side, a motor and blower wheel unit insertable in the case from its lower end and including a blower housing having an inlet and an outlet, means for supporting thel unitin the case in either of two positions to have said outlet communicate with the opening in the case top or the opening in the case side and to have said inlet communicate with the interior of the case in both positions, a discharge fitting adapted for arrangement at either oflsaid openings, and means for securing thefltting to the case at either of said openings.

2. A blower comprising a case having an open side forming the air inlet of the blower and an unit insertable through said open side and comprising' a blower housing having an inlet open to the interior of the case to receive air from the inlet of the blower and an outlet at said opening, a blower wheel in the housing, and a motor at the exterior of the housing for driving the wheel, the motor being out of the path of the air travelling from said open side of the case to the inlet of asiaeee 3. A blowercomprising a case having an open side forming the air inlet of the. blower and an opening in a second side, and a blower wheel unit insertable through said open side and comprising a chambered supporting structure having a f blower chamber Ywith an inlet open to the interior of the case to receiveair from the inlet of the blower and an outlet discharging through vsaid opening, parts on the structure which together with the case walls denne a motor chamber, a motor supported by said structure to be in the motor chamber where it is out of the path of the air travelling said operi side of the case to the inlet of the housing, a blower wheel in the blower chamber driven by the motor, and `means for cooling the motor comprising a louver a blower wheel unit removably inserted through the lower end of the case comprising a pair o spaced generally vertical plates,V volute housings on the outer sides of the plates having inlets at their outer ends communicating with the opposite end portions of the case and having outlets in their sides, the space between the plates forming a, motor chamber, a motor in the chamber supported by the plates and having a shaft extending into the housings, and blower wheels in the housings driven bythe shaft, and means for supporting the unit in the case with said outlets communicating with the openings in the case top or with said outlets communicating with the openings in the case side.

5. A blower of the character described comprising a rectangular case open at its lower end and provided at its top and a side with openings, a blower wheel unit removably inserted through the lower end of the case comprising a pair` of spaced generally vertical plates, volute housings on the outer sides of the plates having inlets at their outer ends communicating with the opposite end portions of the case and having outlets in their sides, the space between the plates forming a motor chamber, a motor in the chamber supported by the plates and having a shaft extending into the housings. and blower wheels in the housings driven by the shaft, and means for supporting the unit in the case with said outlets communicating with the openings in the case top or with said outlets communicating with the openings in the case side, the last named means comprising a cover plate attachable to the case to close the lower end of the chamber and to be engaged by the lower edges ofthe plates with the unit in veither position.

6 A blower of the character described comprising a rectangular case open at its lower end and provided at its top and a side with openings,

inlet, a blower wheel unit removably inserted through the lower end of the case comprising a pair o! spaced generally vertical plates, blower 'nusings on the outer sides of the plates having inlets at their outer ends communicating with the opposite end portions of the case and having outlets in their sides,'1;he space between the plates forming a motor chamber, a motor in the chamber supported by the plates and having a shaft extending into the housings, and blower wheels in the housings drivenby the shaft, a closure and a discharge iitting interchangeably attacnable to the top and side of the case at said openings, the positions of the closure and tting being determined by the position of the unit, and

mcansfor supporting the unit in the case with the open lower end of the case forming the air said outlets communicating with the openings in the case top or with saidoutlets communicating with the openings in the case side.

'1. A blower of the character described comprising a rectangular case open at its lower end and provided at its top and a side with openings,

'a blower wheel unit removably inserted through the lower end or' the case comprising a'pair of spaced generally vertical plates, volute housings on tlie outer sides oi the plates having inlets at their outer ends communicating with the opposite end portions of the case and having outlets in their sides, the space between the plates formhig a motor chamber, a: motor in the chamber supported by the plates and having a shaft extending into the housings, and blower wheels in tile housings driven by the shaft, means for supplying current to the motor comprising disconnectaole plug and socket means in the case accessible through the lower end of the case, and means ior supporting the unit in the case with said outlets communicating with the openings in the case top or with said outlets communicating with the openings in the case side.

8. A blower comprising a case having an open lower end forming the air inlet of the blower and air discharge means, a blower wheel unit insertable through the lower end of the case comprising a pair of spaced plates, housings on the outer sides oi' the plates having discharge passages for communicating with the discharge means, the edges o1' the plates cooperating with the side walls and top w'all of the case so that the space between tlle plates forms a motor chamber, spaced inembeis extending through said chamber and connecting the plates, a motor in the chamber having shafts extending into the housings, vibration danipening and absorbing means mounting tne motor on the members, and blower wheels in the housings driven by the shaft.

9. A blower for installation in a building Wall for use with a discharge duct including a blower wheel, a box-like case receiving the blower wheel and adapted to be iixed in the building wall, the case having an air inlet opening in its lower wall, an opening in its top wall and an opening in one of its side walls, the two last named openings being of similar dimensions, means for mounting the blower wheel in the case to discharge through either of said two last named openings as selected, a closure for either of said two last named openings, a discharge duct adaptor for placing either of said two last named openings in coinmunication with the discharge duct, and means for removably securing the closure and adaptor to either the top wall or said side wall of the case whereby the closure may serve to close either of said last'named openings and the adaptor may put either of said last named openings in communication with the duct, the last named means comprising channel strips on the exterior of the case at each 'of said last named openings for receiving edge portions of the duct adaptor and closure.

10. A blower for installation in a building wall comprising a case to be secured in the wall and having an air inlet aperture in its outer wall, an opening in its inner wall and an opening in one of its side walls, mounting parts on the case at said air inlet aperture adapted to be secured to the wall so that said aperture is open at a face of the wall. an inlet grill for said aperture. a blower wheel unit insertable into the case through fixed in the wall. the unit including an air inlet said air inlet aperture after'the case has been l in communication with the interior oi' the case, a laterally directed discharge nozzle, and a part for engaging in the case to position the unit either where its discharge nozzle directly discharges the air through said opening in the inner wall, or directly discharges the air through said opening in the side wall, means independent of said grill for removably supporting the unit in the case in either of said positions, a closure for either of said openings, a discharge tting for either of said openings, and means for removably securing the closure or the iltting at either of said openings.

WILLIAM M. MARKER. ANDREW G.OREAR. 

